; chapter3 exercise 2
(setf LA '(a b c)
			LB '(b a d))

(defun new-unions (a b)
	(let ((u nil))
		(dolist (n (append a b))
			(if (member n u)
				nil
				(setf u (append u (list n)))))
		u))

(defun new-unions-v2 (a b)
	(let ((u nil))
		(mapcar (lambda (n)
							(if (not (member n u))
								(setf u (append u (list n)))))
						(append a b))
		u))
